printf("This is a Full Maths Program Do you Want to continue......? (Y/N)\n");scanf(" %c", &T);if( (T=='y')||(T=='Y')||(T=='Yes') ){printf("Do You Want to Add, sub, Div, Mul? 'Y,y' If you want to continue or 'N,n' If you want to do some other operations (Y/N)\n");scanf(" %c", &k);

it might be better to set up a queue with a linked list structure to read in numbers and operators. when the user has typed out an equation as a string in stdin and presses enter, it will process the queue and perform the operations on the numbers by first prioritizing operators in order of operations. this way, you dont have to keep prompting the user for numbers and operators.perhaps something like this: